Dir.glob to get all csv and xls files in folder

Question

folder_to_analyze = ARGV.first
folder_path = File.join(Dir.pwd, folder_to_analyze)

unless File.directory?(folder_path)
  puts "Error: #{folder_path} no es un folder valido."
  exit
end

def get_csv_file_paths(path)
  files = []
  Dir.glob(path + '/**/*.csv').each do |f|
    files << f
  end
  return files
end

def get_xlsx_file_path(path)
  files = []
  Dir.glob(path + '/**/*.xls').each do |f|
    files << f
  end
  return files
end

files_to_process = []
files_to_process << get_csv_file_paths(folder_path)
files_to_process << get_xlsx_file_path(folder_path)
puts files_to_process[1].length # Not what I want, I want:
# puts files_to_process.length

I'm trying to make a simple script in Ruby that allows me to call it from the command line, like ruby counter.rb mailing_list1 and it goes to the folder and counts all .csv and .xls files.

I intend to operate on each file, getting a row count, etc.

Currently the files_to_process array is actually an array of array - I don't want that. I want to have a single array of both .csv and .xls files.

Since I don't know how to yield from the Dir.glob call, I added them to an array and returned that.

How can I accomplish this using a single array?

Answer 1

Well, yielding is simple. Just yield.

def get_csv_file_paths(path)
  Dir.glob(path + '/**/*.csv').each do |f|
    yield f
  end
end

def get_xlsx_file_path(path)
  Dir.glob(path + '/**/*.xls').each do |f|
    yield f
  end
end

files_to_process = []
get_csv_file_paths(folder_path) {|f| files_to_process << f }
get_xlsx_file_path(folder_path) {|f| files_to_process << f }

puts files_to_process.length

Every method in ruby can be passed a block. And yield keyword sends data to that block. If the block may or may not be provided, yield is usually used with block_given?.

yield f if block_given?

Update

The code can be further simplified by passing your block directly to glob.each:

def get_csv_file_paths(path, &block)
  Dir.glob(path + '/**/*.txt').each(&block)
end

def get_xlsx_file_path(path, &block)
  Dir.glob(path + '/**/*.xls').each(&block)
end

Although this block/proc conversion is a little bit of advanced topic.